diff --git a/src/gallium/winsys/virgl/vtest/virgl_vtest_socket.c b/src/gallium/winsys/virgl/vtest/virgl_vtest_socket.c
index fb6b27c858f..45f4d88747c 100644
--- a/src/gallium/winsys/virgl/vtest/virgl_vtest_socket.c
+++ b/src/gallium/winsys/virgl/vtest/virgl_vtest_socket.c
@@ -119,7 +119,7 @@ static int virgl_vtest_send_init(struct virgl_vtest_winsys *vws)
 {
    uint32_t buf[VTEST_HDR_SIZE];
    const char *nstr = "virtest";
-   char cmdline[64];
+   char cmdline[64] = { 0 };
    int ret;
 
    ret = os_get_process_name(cmdline, 63);